My light switch literally melted. My garage managed to use a different light switch from a different model but it is not ideal because the number plate light does not turn off and it doesn’t fit. Looking at the internet there are none available. Does anyone know if there is an alternative switch that would work?

You may be lucky enough to find a secondhand original switch in a car breaker's. Many of them are online nowadays.

Thanks. Looking online I only found one which was no longer available at £200!

That's unfortunate, but I don't know what else to suggest.

I would guess the number plate light now being constantly illuminated is the cause of the original switch failure rather than a consequence of the new switch. Melting of the switch would undoubtedly be caused by a high resistance inside it, or else an unusually high current draw. An auto electrician should be able to help.

Hello Harry,

Re. light:- Worth peeling the rubber covering back on the flexible harness section twixt boot/tailgate and the main body. Very often the source of fractured and shorting wires.

Any progress Harry? 

No. Unless I find the exact replacement switch I will have limited control of my lights: no number plate light , no fog lights and headlights on when I switch on the ignition. 

Harry, have a look on the specialist A2 forum - a2oc.net - free to join but there's a £2 charge to access the 'for sale' listings. There are often some spares available but could message A2Steve there as he's always been helpful in the past.